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Item METEOROLOGICAL DROUGHT ANALYSIS: THE CASE OF ABAYA- CHAMO SUB-BASIN(Hawassa University, 2019-03-22) TESHOME AFIRA DULECHAMeteorological drought is the deficit in precipitation over a region for a period of time which in turn results in the reduction of moisture condition of the soil and then the crop yield. It has severe socio-economic and environmental impacts which require to careful monitoring of drought conditions using a suitable index. The objective of this research was to analyze meteorological drought frequency, severity and duration in the Abaya-Chamo Sub-basin using the application of SPI for monthly rainfall records. After checking the data quality and fitting the Gamma statistical distribution for each selected station as a requirement of the SPI, the analysis was done for the past 30 years of record from 1988 to 2017 for five selected stations based on monthly precipitation records using the index at 1-, 3-, 6-, 9- and 12-month timescales. The results show that, no correlation exists between successive observations, and thus, the data are independent, and there was no persistence in the time series. The inter-site correlation was less than one (R2<1) for all the statios and hence all the stations in the sub basin were consistent. For both convectional Cv and L-Cv based homogeneity tests the coefficient of correlation (CC) values were less than 0.3 showing the homogeneity of the stations. Gamma probability distribution was determined as the best fit statistical distribution for the data set since the typical alpha level was greater than 0.05 at 95% of confidence interval as checked using Kolmogorov Smirnov and Shapiro Wilk’s test using SPSS. All of the studied meteorological stations experienced drought episodes in 1988, 1989/1990, 1992/1993, 1999,2000/2001, 2003/2004 and 2007/2008 which were among the worst drought years in the history of Ethiopia, and moderate drought events ranging from the SPI values of -1.49 to -1 were pronounced with greater frequency than other dry events. Severely dry events were occurred at values between -1.99 and -1.50. The maximum SPI value of extreme dry event was -2.69. The year 1999 was the most drastic and distinct-wide extreme drought episode in all studied stations. The findings of this study have implications for drought management, early warning system, preparedness and contingency planning and climate change adaptationItem ANALYSIS AND PRIDICTION OF METEOROLOGICAL DROUGHT USING STANDARDIZED PRECIPITATION INDEX: CASE STUDY OF EASTERN OROMIA(Hawassa University, 2019-02-14)Ethiopia is one of the most drought affected country in Africa and suffered from acute drought many time in recent years. The objective of this study is to understand the rainfall variation and conduct an in-depth analysis and prediction of drought for to Eastern Oromia. Standardized precipitation index (SPI) was selected to characterize drought condition in the region. Drought characteristics at a time scale of 2-month, 3-month, 6month and 12-month were computed separately for 22 selected rain gauge station. The most maximum drought characteristics at 2-month, 3-month, 6-month and 12-month time scales have been found in Hararegie over last 36 years (1979-2015). The spacial extent of drought and rainfall variation were determined from SPI and CV values computed separately for each rainfall have been interpolated between station in Arc view GIS environment. The rainfall variation shows that the rainfall over the study area is highly variable and increases from Arsi to East Harargie and in the recent last decade (2005-2015) the map of SIP-3 (Belg) shows that a spacial extent drought over study area was irregular and there were no period in recent decades (2005-2015) without drought at least mild drought and this shows that the area is vulnerable to drought. The maximum intensity of (5.33) was recorded at Fedis Station for SPI-3 (kiremt season) in a year 1996, maximum intensity of (4.04) was recorded at Kobo Station in a year 1985 for SPI-3 (Belg season), maximum intensity of (4.77 and 4.5) were recorded at Ticho Station for SPI-6 (both seasons) and SPI-12 (annual) respectively. The drought prediction was made until 2043, using the Representative Concentration Path way (RCP) 8.5 Scenario.on the basis of the drought index measured by SPI. From the analysis of the drought index through the RCP 8.5 Scenario, extreme drought intensity will be more likely to occur. The long-term forecast (12-month period unit) showed that extreme drought would occur severely at station Diksis Sude, Hirna and Adelle from 2035 to 2040 and need more attention for this area